Forum Discussion
wa8yxm
Jul 30, 2015Explorer III
Are you asking if you can replace a pair of group 27 with a pair of GC-2 assuming you have the height.
Only if you want around 30-50 more amp hours and close to double the USABLE amp hours. (in short very good idea)
Here is what you need to know:
MARINE/deep cycle batteries are first and foremost starting batteries, Running them down to 50 percent SOC does major damage.
DEEP CYCLE are desiened to run down to 50%. GC-2's are DEEP CYCLE
WIth Group 27s you can replace just one.. most of the arguments against doing that are ... not supported by observation or fact.
With GC-2's you MUST replace both of the paired batteries (if you have multiple pairs this applies only to the batteries in a pair.. NOT to the next pair)
THERE ARE NO SIX VOLT BATTERIES IN AN RV
I know, the CC-2 is a six volt battery.. But when you hook that jumper up from Battery one to battery 2, Electrical magic happens and the two of them together become a single 12 volt battery (roughly a 4D)
-Battery 1+=Jumper=-Battery 2+ 12 volts
Think of the pair as a single 12 volt battery and watch questios vanish
How do I charge them (you charge it same as you would any other 12 volt battery)
Can I replace just one (Can you replace half a 12 volt battery)
and so on.
Only if you want around 30-50 more amp hours and close to double the USABLE amp hours. (in short very good idea)
Here is what you need to know:
MARINE/deep cycle batteries are first and foremost starting batteries, Running them down to 50 percent SOC does major damage.
DEEP CYCLE are desiened to run down to 50%. GC-2's are DEEP CYCLE
WIth Group 27s you can replace just one.. most of the arguments against doing that are ... not supported by observation or fact.
With GC-2's you MUST replace both of the paired batteries (if you have multiple pairs this applies only to the batteries in a pair.. NOT to the next pair)
THERE ARE NO SIX VOLT BATTERIES IN AN RV
I know, the CC-2 is a six volt battery.. But when you hook that jumper up from Battery one to battery 2, Electrical magic happens and the two of them together become a single 12 volt battery (roughly a 4D)
-Battery 1+=Jumper=-Battery 2+ 12 volts
Think of the pair as a single 12 volt battery and watch questios vanish
How do I charge them (you charge it same as you would any other 12 volt battery)
Can I replace just one (Can you replace half a 12 volt battery)
and so on.
About Technical Issues
Having RV issues? Connect with others who have been in your shoes.24,363 PostsLatest Activity: Mar 04, 2026